Parquet, Hadoop-BAM integration, Hadoop 1/2 support

o ADAM now generates Avro records and stores them in Parquet files.
o Conversion from genomic file formats to Avro is now done using
  Hadoop Map-Reduce (instead of only local)
o ADAM now runs with any version of Hadoop
o Support for FASTA files has been added
o Cleaned up the way Avro generate source is handled
o Added optional BAM attributes to ADAM format
Add a simple pig script example
FastaInputFormat should have isSplitable() return false always
New pileup and faster print command

NEW FEATURES

  New pileup command that creates a reference-ordered data file sorted
  by position with the reference base and pileup (including phred scores)
  at each position

IMPROVEMENTS

  The print command is simplified and no longer launches a map-reduce job.
  Contents of files are now immediately streamed to console.

  Added the unique record group identifier to ADAM read records

BUG FIXES

  Fixed the read file format to use 0-based (instead of 1-based) offsets
  for read positions. All ADAM files are 0-based.
Convert the project to a multi-module project

This change will make it easier to publish artifacts targetted
at integration with other systems like GATK.